for safe anchorage. The islands on the southern margin of the Louisiade Archipelago are raised coral reefs, but the majority are mountainous, rarely, however, exceeding 3000 ft.; all of them are richly forested, but of little agricultural value. The volcanic d’Entrecasteaux Islands are mostly larger, more elevated (the highest being 8000 ft.), and stand in deeper water than the Louisiade group. To the east of Kiriwina (Trobriand) lies a small group of uniquely formed islets, each of which is completely surrounded by a steep forest-clad marginal rampart of coral 300 to 400 ft. high, concealing a depressed inhabited central plateau.
Starting in the southern extremity of New Guinea from an abrupt face some 3000 ft. high, and traversing its centre nearly parallel to both coasts, run high ranges of mountains, which, if not continuous, merge into each other in the same general direction. The Owen Stanley range—its highest summit, named by Huxley in 1850 Mount Owen Stanley, 13,120 ft.—the Albert Victor Mountains, the Sir Arthur Gordon range, and the Bismarck Mountains form a backbone united probably with the Sneeuw (Snowy) Mts., where perpetual snow was found by Dr. Lorentz in 1909 at 14,635 ft., and the height of Mt. Wilhelmina was fixed at 15,580 ft. This height may be exceeded by Mt. Carstensz. Other ranges, mostly of lower altitude, run parallel mainly to the east and west coasts. The most important and best-known rivers are the Amberno, in the north, discharging by a wide delta at Point d’Urville; the Kaiserin Augusta, which, rising in the Charles Louis range, and entering the Pacific near Cape della Torre, is navigable by ocean steamers for 180 m.; the Ottilien, a river of great length, which discharges into the sea a short distance south of the last named; and the Mambare, navigable by steam-launch for 50 m. which drains the eastern aspect of Wasigororo Mountains and enters the sea near the Anglo-German boundary. Below 8° S. the narrowness of the country precludes the existence of any very important rivers on either coast. The Purari, however, whose delta is 20 m. long by 20 broad, is navigable for 120 m. by steam-launch, while the Fly has been traversed by the same means for 500 and by a whale-boat for over 600 m. The latter drains an enormous tract of country, which is so little elevated above the sea-level that it can never be of any agricultural or commercial value. West of 141° E. the geographical features of the coast, except in the region of MacCluer Inlet and Geelvink Bay, are very little known, and those of the interior even less.
Geology.—The geology of British New Guinea is best known from the report of A. Gibb Maitland (Ann. Rep., British New Guinea, 1891–1892; Parl. Papers, Queensland, 1893, C.A. l. 53-85, with 3 maps and 3 plates; bibliography, p. 35). which shows that the axis of the territory is a high range, composed of slates and schists of undetermined age, with intrusive plutonic rocks. In the district around Port Glasgow, on the south coast of the eastern peninsula, are the Boioro limestones, also of unknown age; they are lead-coloured, brecciated limestones with interbedded dolerites. Some Cretaceous or Upper Jurassic rocks occur in the basin of the Fly river. The Port Moresby beds are Cainozoic. They are highly inclined, and occupy a large range of country along the south coast, and include the Macgillivray Range, to the north-east of Beagle Bay. They are marine and probably Miocene; and range up to the height of 800 ft. above the sea, approximately the same limit as in Victoria. The Kevori grits, and the raised coral reefs are upper Cainozoic, and perhaps Pleistocene; but the reefs occur inland up to a height of 2000 ft. and their range back in time has not been fixed. The volcanic series include the rhyolite of Nell Island, some obsidian, and the sheets of basalts which form the Cloudy Mountains, Mount Dayman and Mount Trafalgar (an active volcano), and also cover wide areas to the south and west of the Owen Stanley Range. Most of western British New Guinea consists of recent superficial deposits, in the basin of the Fly river. The Louisiade and the d’Entrecasteaux Islands consist of the same slates and schists as form the main axis of the eastern peninsula, and they are auriferous. The geology of the rest of New Guinea is imperfectly known. It appears to consist in the main of a continuation of an axis of old schists and slates, with granite intrusions, and flanked by coastal plains with Cretaceous or Jurassic, and Miocene beds, with Pleistocene sands and reefs and volcanic rocks. In the north-west coal deposits occur. Fergusson Island clearly shows remains of extinct craters, and possesses numerous hot springs, saline lakes and solfataras depositing sulphur and alum. In Murua (Woodlark I.) are quarries of the banded quartzite from which the best stone adzes found throughout south-east New Guinea are made. In Rossel Island (Roua or Arova) occur crystalline schistose and volcanic rocks, and in Misima (St Aignan) limestones and lavas in addition. Nearly all the rivers in New Guinea yield "colours" of gold, but only in the Louisiade Archipelago has enough been discovered to constitute the district a goldfield. No auriferous reefs have been found. Black magnetic iron sand covers the shore in Milne Bay. Coal has been observed in the Purari sandstones. In the Gira river the valuable alloy osmiridium has been discovered. Earthquakes are rare on the mainland, but not infrequent in Bismarck and d’Entrecasteaux archipelagos.
Climate.—Since the mountains as a rule traverse the island parallel to its coasts, the eastern shores have far less rain than the western. The amount which falls, chiefly at night, varies from 30 in. on some parts of the coast to 130 at others, and to a far greater but unknown amount in the mountains. Throughout the dry or cool season the wind blows steadily and almost uninterruptedly (except for an hour or so forenoon and afternoon) from the south-east. The temperature
